Break-resistant anode assemblies for cathodic protection systems and methods of installing the same

ABSTRACT

Various break-resistant anode assemblies and method of installing the same in the ground are disclosed. Each anode assembly ( 20 ) basically comprises an anode ( 22 ), at least one pulling cable ( 24 ), and a protective nose cone ( 26 ). The nose cone is a hollow member receiving the leading end ( 22 A) of the anode and from which the anode&#39;s electrical conductor ( 28 ) extends. The nose cone includes a tapered leading surface ( 32 ) that facilitates and guides the anode assembly as it is pulled through the ground, while protecting the anode. A break-away mechanism ( 54 ) may also be provided to ensure that no more than a maximum pulling force is applied to the anode assembly during its installation to ensure that the anode is not damaged.

CROSS-REFERENCE TO RELATED APPLICATIONS

This PCT application claims the benefit under 35 U.S.C. §119(e) ofProvisional Applications Ser. No. 61/751,069, filed on Jan. 10, 2013,entitled Break-Resistant Anode Assembly For Cathodic Protection SystemsAnd Method Of Installing The Same and Ser. No. 61/762,549, filed on Feb.8, 2013, entitled Break-Resistant Anode Assembly For Cathodic ProtectionSystems And Method Of Installing The Same, whose entire disclosures areincorporated by reference herein.

FIELD OF THE INVENTION

This invention relates generally to cathodic protection systems and moreparticularly to break resistant anode assemblies for horizontaldirectional drilling applications and methods of installing the same.

BACKGROUND OF THE INVENTION

Cathodic protection systems commonly make use of packaged linear anodeshaving a variety of shapes (e.g., round, flat, or other shapes) and maybe either a polymeric cable anode or a Mixed Metal Oxide (MMO) wireanode housed inside a braided or unbraided fabric housing filled withconductive backfill. These commercially available fabric-based linearanodes are similar in design and function. One particularly usefulpackaged linear anode for cathodic protection systems is commerciallyavailable from Matcor, Inc., the assignee of the subject invention,under the trademark SPL-FBR.

Increasingly, linear anodes are being used in conjunction withhorizontal directional drilling (HDD) technology for installation. Whilesuch prior art anodes are suitable for various applications, they arenot particularly suited for HDD applications inasmuch as they are proneto damage if the pulling force applied to them exceeds the pull strengthof the packaged linear anode assembly. Thus, various techniques havebeen developed or used to attempt to minimize the potential fordamaging/breaking conventional socked linear anodes during installation.One such technique entails making use of a separate, larger diametercable with greater pull strength in conjunction with the packaged linearanode and pulling them together through the hole. Another techniqueentails using an oversized drill hole and additional drilling fluids totry and lubricate the hole (“muddying up the hole”) to reduce thepulling stress on the packaged linear anode. Still another techniqueentails using an in-line breakaway swivel to protect against overpulling the anode during installation. Yet another technique entailsinstallation of a temporary plastic conduit pipe to case the hole andthen pulling the anode through the conduit pipe casing. Once installed,the casing is pulled back out and can be reused for another pull whilethe anode remains in place.

All of these are workaround solutions that attempt to overcome theinherent design weaknesses of all current packaged linear anode productsto available on the market. Thus, a need exists for an anode assemblywhich overcomes the disadvantages of the prior art.

The subject invention addresses that need. In particular, the subjectanode assembly is designed specifically for HDD installation andincorporates a special pulling head or nose cone and integral pullingcable system, e.g., two pulling cables, to significantly increase thepulling strength of the assembly to minimize the possibility of itbreaking during installation using HDD equipment.

SUMMARY OF THE INVENTION

In accordance with one aspect of this invention an anode assembly, isprovided for a cathodic protection system. The anode assembly arrangedto be pulled through the ground for installation in the cathodicprotection system and basically comprises an anode, a nose cone, and atleast one pulling cable. The anode comprising an elongated body having aleading end portion from which an electrical conductor extends and atrailing end portion from which an electrical conductor extends. Thenose cone comprises a tubular member having a leading portion and atrailing portion. The leading portion has an open free end and asidewall portion tapering in a direction from the trailing portiontowards the open free end. The nose cone is fixedly secured to the atleast one pulling cable. The leading end portion of the anode is locatedwithin the nose cone with the electrical conductor extending out of theopen free end. The at least one pulling cable has a leading portion anda trailing portion. The trailing portion of the at least one pullingcable extends along at least a portion of the length of the anode andthrough the nose cone, with the leading portion of the at least onepulling cable extending out of the open free end of the nose cone toenable the anode assembly to be pulled through the ground by a pullingforce applied thereto.

In accordance with one aspect of this invention the anode assemblycomprises a braided sleeve comprising a first plurality of closelyadjacent coils, with the first plurality of closely adjacent coilsforming the sidewall portion of said nose cone.

In accordance with another aspect of this invention the cone is a solidtubular member and the anode assembly comprises a braided sleeve, with aportion of the braided sleeve forming the at least one pulling cable.

In accordance with another aspect of this invention the anode assemblyhas a predetermined pulling strength and the anode assembly additionallycomprises a break-away mechanism connected to the portion of the atleast one pulling cable and arranged to break if the predeterminedpulling strength is reached to prevent damage to the anode assembly.

In accordance with another aspect of the invention there is provided amethod of installing an anode within the ground for a cathodicprotection system. That method basically entails providing an anodeassembly comprising an anode, a nose cone, and at least one pullingcable, with the anode comprising an elongated body having a leading endportion from which an electrical conductor extends and a trailing endportion from which an electrical conductor extends, with the nose conecomprising a tubular member having a trailing portion and leadingportion having an open free end, and with the leading portion of thenose cone tapering in a direction from the trailing portion of the nosecone towards the open free end. The leading end portion of said anode isdisposed within the nose cone with the electrical conductor extendingout of the open free end and with the at least one pulling cableextending along at least a portion of the length of anode and throughthe nose cone, whereupon a leading portion of the pulling cable extendsout of the open free end of the nose cone. The nose cone is fixedlysecured to the at least one pulling cable. After that has beenaccomplished, the cable assembly is disposed within the ground and apulling force is applied to the leading portion of the at least onepulling cable to pull the anode assembly through a path in the ground toeffect its installation.

DESCRIPTION OF THE DRAWING

FIG. 1 is a side view, partially in section, of one exemplary embodimentof a break resistant anode assembly constructed in accordance with thisinvention;

FIG. 2 is a view similar to FIG. 1 but showing more details of theinterior of the anode assembly of FIG. 1, e.g., the anode, two pullingcables, a clamp and a protective nose cone;

FIG. 3 is an enlarged sectional view taken along line 3-3 of FIG. 2showing the clamp of the anode assembly;

FIG. 4 is a sectional view, like that of FIG. 3, but showing the clampin its open state;

FIG. 5 is a side view showing a portion of the anode assembly of FIG. 1shown including an optional tape wrapping;

FIG. 6 is a longitudinal sectional view of preferred nose cone includingtwo pulling cable guides forming a portion of the assembly of FIG. 1;

FIG. 7 is an enlarged sectional view taken along line 7-7 of FIG. 6, butwith respective pulling cables shown disposed within respective pullingcable guides;

FIG. 8 is a side view, partially in section, of an alternative anodeassembly including;

FIG. 9 is a view similar to FIG. 7, but showing the leading end of theassembly of FIG. 7 with a heat shrink sleeve disposed about the leadingend portion of the assembly;

FIG. 10 is a side view partially in section of still another alternativeanode assembly in accordance with this invention, with this embodimentalso making use of a break-away mechanism arranged to break if thepulling strength of the anode assembly is exceeded; and

FIG. 11 is a side view partially in section of another, and mostpreferred, alternative anode assembly in accordance with this invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the various figures of the drawing wherein likereference characters refer to like parts, there is shown at 20 in FIG. 1one exemplary embodiment of an anode assembly 20 constructed inaccordance with the subject invention. The assembly 20 basicallycomprises an anode 22, at least one pulling cable 24 and a protectivenose cone 26. The anode 22 can be of any suitable construction. In onepreferred embodiment it comprises a SPL-FBR anode available from Matcor,Inc. That anode is a MMO linear anode that is factory packaged with cokebackfill in a porous, cloth housing. The anode includes an electricalconductor 28, a portion of which extends out the leading end 22A (FIG.2) of the anode 22 and another portion of which extends out of thetrailing end 22B of the anode. The anode 22 can be of any length, from10 feet to lengths of more than 1,000 feet.

In the exemplary embodiment shown the at least one pulling cable 24comprises two identical pulling cables 24A and 24B. It should be pointedout at this juncture that such an arrangement is merely exemplary. Thus,the anode assembly of this invention can make use of one, two, three ormore pulling cables. If more than one pulling cable is used, they areextended parallel to each other and preferably equidistantly spaced fromeach other. Irrespective of the number of cable(s) used, it(they) is/arearranged to have a pulling force applied to it/them to pull the anodeassembly through the ground, e.g., through drilled soil. To that end,each of the cables used includes a leading or upstream end to which thepulling force may be applied, and trailing or downstream end.

The nose cone 26 is mounted on the leading end of the anode 22. The nosecone serves to protect the anode as it is pulled through the ground bythe pulling cables. In addition, the nose cone 26 provides a guide forthe anode 22, the conductor cable 28 and the pulling cables 24A and 24B.To that end, the nose cone 26 is shaped to provide a clearing mechanismas the assembly is pulled through drilled soil. In particular, as bestseen in FIGS. 1, 2, 6 and 7, the nose cone basically comprises a hollow,solid-walled tubular member, formed of a strong and impact resistantmaterial, e.g., steel. It includes a trailing end portion 30 and aleading end portion 32. The trailing end portion 30 comprises a circularside wall 30A (FIGS. 1 and 7), the inside diameter of which is slightlylarger than the outside diameter of the anode 22. The leading endportion 32 of the nose cone is in the form of a tapering, e.g., conical,side wall 32A having an open free end 34 (FIG. 2). The side wall 32tapers in a direction from the trailing end portion 30 of the nose conetowards the open free end 34. In the exemplary embodiment shown the freeend of the nose cone is in the form of a circular side wall 36, whosediameter is less than that of the trailing end portion of the nose coneand whose free end is open at 34. The nose cone can be fabricated invarious ways. For example, it may be made up of two individualcomponents, i.e., the trailing end portion and the leading end portion,which are welded together along a peripheral weld line 38 (FIG. 6) toform an integral unit, or it may be directly formed as an integral unit.

The two pulling cables 24A and 24B are secured to and extend parallel toeach other along the entire length of the anode 22. The securement ofthe cables to the anode is achieved by means of one or more clamps 40(to be described later). The cables 24A and 24B are formed of strong,yet somewhat flexible material, e.g., steel, or other metals ornon-metals, and each is of a small diameter, e.g., 0.25 inch, so that itmay easily fit with the anode within the trailing end portion 30 of nosecone 26. It is also contemplated that the pulling cables may be locatedwithin the body of the anode, instead of extending outside of it. In anycase, the leading end portions of each of the pulling cables 24A and 24Bextend out of the open free end 34 of the nose cone 26, with thoseportions extending parallel to each other and with the leading end ofthe electrical conductor 28 interposed therebetween. The length of theleading end portions of the pulling cables and the leading end portionof the electrical conductor exiting from the free end of the nose conecan be whatever is desired for the particular application. In oneexemplary embodiment of this invention those portions of the pullingcables and electrical conductor are 10 feet long.

As best seen in FIGS. 1 and 2 an external braiding 42, such as PVCcoated high strength yarn (e.g., like the type used in the MatcorSPL-FBR anode), is disposed about the leading end portion of the anodeand the portion of the pulling cables 24A and 24B disposed within thenose cone and for some length of the anode and cables located downstream(to the rear) of the nose cone. In particular, for one exemplaryembodiment of this invention, the first twelve inches measured of theleading end portion of the anode is covered with a double wrap braiding42A, while the remainder of the anode is covered by a single wrapbraiding 42B.

As shown in FIG. 5, the trailing end portion of the nose cone and aportion of the assembly located immediately downstream (i.e., to therear) of the nose cone may be covered by a tape wrapping 45 for cosmeticpurposes. The tape can be any suitable material, such as PVC tape, vinyltape, etc.

Turning now to FIGS. 6 and 7, the details of one exemplary embodiment ofa nose cone constructed in accordance with this invention will now bedescribed. That nose cone includes a pair of elongated channel-likeguide members 44A and 44B extending parallel to each other alongdiametrically disposed portions of the side wall 30 making up thetrailing end of the nose cone 26. Each of those guide members is formedof steel or some other material and includes a raceway 46 adapted toreceive a portion of an associated pulling cable to ensure that thepulling cables remain spaced from each other.

As mentioned earlier the clamp 40 is provided to secure the nose cone tothe cables 24A and 24B. The clamp 40 is located abutting the trailingend of the nose cone 26 and, like that portion of the nose cone, iscovered by the double braiding 42A. As best seen in FIGS. 3 and 4, theclamp basically comprises a clam-shell like body having a pair ofpivotably connected members 40A and 40B which are arranged to be movedfrom an open position like shown in FIG. 4 to a closed position likeshown in FIG. 1 to tightly sandwich the cables between it and the anode.To that end, the members 40A and 40B are connected via a hinge 48. Eachmember 40A and 40B includes a semi-circular recess 50 (FIG. 4), whichwhen the members are in the closed position conjoin to form a circularopening whose inside diameter is approximately the same as the outsidediameter of the anode to accommodate the anode therein. Each of themembers 40A and 40B also include a pair of diametrically opposed smalldiameter semi-circular recesses 52 (FIG. 4), which when the members arein the closed position conjoin to form a pair of circular openings whoseinside diameter is approximately the same as the outside diameter of thepulling cables 24A and 24B to accommodate respective ones of the cablestherein.

As should be appreciated by those skilled in the art when the clamp 40is in the closed position it is fixedly secured to the anode 22 and tothe pulling cables 24A and 24B. Thus, since the clamp 40 is locatedabutting the trailing end of the nose cone 26, any pulling force appliedto the leading end of the cables will be transferred to the nose cone,thereby pulling the assembly 20 as a unit through the ground. Inaddition, if desired, a plurality of clamps can be used located atequally spaced points along the length or a portion of the length of theanode to connect the anode to the pulling cable (s) at those points andthus distribute the pulling force applied to the assembly.

Turning now to FIGS. 8 and 9 there is shown another exemplary embodimentof the invention. That assembly is designated by the reference number20′ and is basically the same construction as the assembly 20 describedheretofore, except for the inclusion of a break-away mechanism 54 toensure that the pulling force applied to the assembly will not exceed apredetermined pulling strength which could damage the anode assembly.Since the assembly 20′ is of the same construction as assembly 20 thecommon details of those assemblies will be given the same referencenumbers and will not be discussed further in the interest of brevity.The break-away mechanism basically comprises a body 56 in which abreakable link 58 is located. The trailing end of the breakable link isfixedly secured to a swivel 60A, while the leading end of the breakablelink is fixedly secured to a swivel 60B. The swivel 60A is in turnfixedly secured to the leading end of the two pulling cables 24A and24B. The swivel 60B is in turn fixedly secured to the trailing end ofanother pulling cable 24C. The cable 24C is similar to the cables 24Aand 24B and serves as the means for applying a pulling force to thebreak-away mechanism and hence to the anode assembly 20′. The linkbreakable link 58 is chosen to have a breaking strength at a level,e.g., 1500 lbs., which will ensure that the breaking strength of theanode is not exceeded when a pulling forced is applied to the pullingcable 24C. In particular, if an excessive pulling force is applied, thebreakable link 58 will break, thereby preventing any damage to theanode.

In accordance with one exemplary embodiment of this invention thebreakable link and its associated swivels is purchased as a unit fromCondux, International, Inc., under its model numbers 08021500, 08019400,08019500, with a break-load between 1,000 and 2,000 pounds. Other unitsfrom other suppliers can be used as well. Irrespective of the unit, itis disposed within the housing 56, which is formed of any suitableplastic material, preferably molded in two halves and secured to eachother to form a hollow interior in which the breakable link unit isdisposed, and which is approximately 7 inches long and 1.5 inches inoutside diameter. In order to facilitate the pulling of the assembly 20′through the ground the housing 56 is in the general shape of a submarinehaving a tapered leading end and a tapered trailing end. The break-awaymechanism 54 can be located any distance from the nose cone 26. In theabove described exemplary embodiment it is located approximately tenfeet in front of the nose cone and the portion of the extending pullingcables 24A and 24B and the extending electrical conductor 28 up to thetrailing end portion of the break-away mechanism's housing 56 ispreferably covered and protected by a heat shrink tubing 62.

Turning now to FIG. 10 there is shown another alternative embodiment ofthe anode assembly 100 of this invention. The assembly 100 isconstructed similarly to the anode assemblies 20 and 20′ except that thepulling cable of the anode assembly 100 is formed of a braided sleeve(to be described shortly). In the interest of brevity the components ofthe assembly 100 which are common to the assemblies 20 and 20′ will begiven the same reference numbers and all of the details of theirconstruction and operation will not be reiterated. Thus, as can be seenin FIG. 10 the assembly 100 basically comprises an anode 22, a singlepulling cable 124 and a protective nose cone 126. The anode includes anelectrical conductor 28, a portion of which extends out the leading end22A of the anode 22 and another portion of which extends out of thetrailing end of the anode. The nose cone 126 is similar in many respectsto the nose cone 26, i.e., is a solid-walled tubular member, but is ofslightly different shape, e.g., it is of a bullet-like shape whoseleading tapered end is rounded. Moreover, it doesn't include anychannel-like guide members 44A and 44B since it makes use of a singlepulling cable 126

In the exemplary embodiment shown the pulling cable basically comprisesa braided sleeve 124 which extends for the entire length of the anode 22over the PVC braiding 42. If desired, a clamp 40 can be used to securethe braided sleeve 124 to the nose cone 126. The wire strands making upthe braided sleeve 124 constrict or merge towards each other as theyexit the open end 36 of the nose 126 cone to thereby form a singlebraided cable 124A. The wire strands making up the braided sleeve arepreferably carbon steel and can be coated, if desired, with brass ornickel, or may be formed of stainless steel or any other strong,flexible non-steel material, such as carbon fiber. The braided sleevemay be single or multi-stranded. In one exemplary embodiment the braidedsleeve 124 is multi-stranded, e.g., formed of six strands of hightensile strength steel wire, each having a diameter of approximately0.012 in. That sleeve is similar to conventional braided washing machinehoses. A braided sleeve constructed in that manner provides very goodstability and pull strength, e.g., up to 1,200 lbs. or more.

The leading end of the anode conductor 28 exits the nose cone 126, viathe open end 36, and extends parallel to the braided cable 124 forconnection to the cathodic protection system.

The leading end of the braided cable 124A is connected to the swivel 60Aforming a portion of the break-away mechanism 54 (the remainder of whichmechanism is not shown in FIG. 10). In particular, the free end of thebraided cable 124A is threaded through the swivel 60A and looped backover itself and secured in place by one or more cable clamps 130. Theother swivel 60B of the break-away mechanism 54 is connected to anotherpulling cable, e.g., like cable 24C, as described with respect to theembodiment 20′. The break-away mechanism 54 can be located any distancefrom the nose cone 126. In the above described exemplary embodiment itis located approximately 10 feet in front of the nose cone and theportion of the extending braided pulling cable 124A the extendingelectrical conductor 28 up to the trailing end portion 124A of thebreak-away mechanism's housing 56 is preferably covered and protected bya heat shrink or other tubing 62 that houses the cables exiting the nosecone for connection to the swivel and providing strength for the wireclamp(s) connected to the cable. If desired, a section of steel cable,not shown, may be included in the last four feet of the hollow braidedcable to provide additional strength for the connection to the swivel60A.

Turning now to FIG. 11 there is shown another alternative, and mostpreferred, embodiment of the anode assembly 200 of this invention. Theassembly 200 is constructed similarly to the anode assembly 100, exceptfor the construction of the nose cone and the pulling cable. In theinterest of brevity the components of the assembly 200 which are commonto the assembly 100 will be given the same reference numbers and all ofthe details of their construction and operation will not be reiterated.Thus, as can be seen in FIG. 11 the assembly 200 basically comprises ananode 22, a single pulling cable 202 and a protective nose cone 204. Thenose cone 204 is formed by portion of a braided sleeve 206. The braidedsleeve 206 extends for the entire length of the anode 22 over the PVCbraiding 42 and in tight engagement therewith. The braided sleeveincludes a leading portion 206A, a trailing portion 206B and anintermediate portion (not shown). The leading portion 206A of thebraided sleeve is tightly braided, i.e., is formed by a first pluralityof closely adjacent coils of the wires making up the braid. This tightlybraided portion of the sleeve forms the nose cone 204, whose leadingfree end is open. The braided portion of the sleeve forming the nosecone 204 is located over the leading end portion of the anode 22. Thetrailing portion 206B of the braided sleeve is formed by a secondplurality of closely adjacent coils of the wires making up the braid andis located over the trailing end portion of the anode 22 and terminatesin an open trailing free end. The intermediate portion of the braidedsleeve is located between the leading portion 206A and the trailingportion 206B and is made up of a plurality of wider spaced coils of thewires making up the braid. The wires making up the braid can be of anysuitable construction, one exemplary preferred material comprises 28gauge stainless steel (type 304) wires.

The anode 22 includes an electrical conductor, a portion of which 28Aextends out the leading end 22A of the anode 22 and through the openleading free end of the nose cone 204. The electrical conductor includesanother portion 28B which extends out of the trailing end of the anodeand through the open trailing free end of the braided sleeve. The freeend of the leading conductor 28A is covered by a removable protectivecap 208. The free end of the trailing conductor 28B is also covered by aremovable protective cap 208. The caps 208 can be formed of any suitablematerial, e.g., a plastic or metal, and serve to protect the free end ofthe conductor on which they are mounted as the anode assembly is pulledthrough the ground during the installation. After that has beenaccomplished the caps can be removed to effect the electrical connectionof the anode to the cathodic protection system.

The pulling cable 202 of the assembly 200 basically comprises a strongcable formed of any suitable material, e.g., 0.25 inch aircraft steelcable, which is over-braided with a metallic braid. Other suitablematerials can be used in place of that type of cable. In any case, thecable 202 extends a substantial distance, e.g., 5 feet, from the leadingend of the anode toward the trailing end of the anode. The cable is heldtightly in place between the PVC braiding 42 on the anode and the innersurface of the wires making up the braided sleeve 206. To further securethe cable to the braided sleeve and the anode, the trailing end of thecable 202 includes a section of a heat shrink sleeve 210 tightlysurrounding the trailing and of the cable. The heat shrink sleeve 210 isadhesively secured by a hot melt glue 212 (or any other suitableadhesive) to the inner surface of the braided sleeve 202 and the outersurface of PVC braid 42 on the anode.

In the exemplary embodiment of the anode assembly 200, the pulling cableincludes a looped leading end portion 214. That loop is optional. Ifused, the loop 212 is formed by bending back the free leading end 202Aof the pulling cable 202 securing it to another portion of the cable byuse of a pair of crimp sleeves 216. Those crimp sleeves 216 can beformed of any suitable material, e.g., aluminum. If desired, the anodeassembly 200 may make use of a break-away mechanism, like that describedabove. In any case the installation and use of the anode assembly 200 isaccomplished in a similar manner to that described above.

As should be appreciated from the foregoing, the anode assemblies ofthis invention include various features that can significantly increasethe anode's pulling strength and make it much more resistant to damage,thereby facilitating their installation The first feature is the use ofone or more integral pulling cables attached to the packaged linearanode assembly. The pulling cable(s) consist of one or more pullingcables extending from the front of the anode or some distance along thelinear anode. The pulling cable(s) is/are of smaller diameter cable thanthe linear anode package. The cable(s) are of steel, other metals ornon-metallic cables and are mechanically secured to the packaged anodeassembly. The cable(s) can run on the outside of the anode or could beembedded inside the anode. The pulling cable can also be formed by useof a braided sleeve which covers the anode and which has a leadingportion extending from the leading end of the anode.

The second feature is a nose-cone. The nose-cone has particular utilitywhen used in conjunction with an anode like the Matcor SPL-FBR anode orother similar type anodes. In this regard, the nose-cone provides aguide for the anode, the conductor cable and the pulling cable(s). Thenose-cone's shape provides a clearing mechanism as the anode assembly ispulled through drilled soil. The nose cone is preferably formed by useof a braided sleeve, whose leading portion is tightly braided to formthe nose cone. The braided sleeve in such a case extends the wholelength of the anode, with a trailing end portion of the sleeve alsobeing tightly braided to cover the trailing end portion of the anode,and with a looser braided intermediate portion located between theleading and trailing portions of the braided sleeve. Alternatively, thenose-cone may be formed of a solid walled tubular member which tapers inthe direction of its leading end and which terminates in an open endthrough which the pulling cable and the anode's conductor can extend. Inthat type of arrangement the pulling cable may be formed by a braidedsleeve as discussed above.

The third feature is an integral break-away mechanism, e.g., itscalibrated pin or link, that will fail before the anode assembly pullingstrength is exceeded. Should the pull force exceed the rated maximumpull strength of the calibrated pin on the breakaway mechanism, the pinwill break preventing the anode assembly from being pulled further intothe drilled hole and protecting the anode assembly from damage.

Thus, it should be clear to those skilled in the art that anodeassemblies constructed in accordance with this invention areparticularly well suited for HDD installation.

Without further elaboration the foregoing will so fully illustrate ourinvention that others may, by applying current or future knowledge,adopt the same for use under various conditions of service.

We claim:
 1. An anode assembly arranged to be pulled through the groundfor installation in a cathodic protection system, said anode assemblycomprising an anode, a nose cone, and at least one pulling cable, saidanode comprising an elongated body having a leading end portion fromwhich an electrical conductor extends and a trailing end portion fromwhich an electrical conductor extends, said nose cone comprising atubular member having a leading portion and a trailing portion, saidleading portion having an open free end and a sidewall portion taperingin a direction from said trailing portion towards said open free end,said nose cone being fixedly secured to said at least one pulling cable,said leading end portion of said anode being located within said nosecone with said electrical conductor extending out of said open free end,said at least one pulling cable having a leading portion and a trailingportion, said trailing portion of said at least one pulling cableextending along at least a portion of the length of said anode andthrough said nose cone, with said leading portion of said at least onepulling cable extending out of said open free end of said nose cone toenable said anode assembly to be pulled through the ground by a pullingforce applied thereto.
 2. The anode assembly of claim 1 wherein saidnose cone comprises a braided sleeve comprising a first plurality ofclosely adjacent coils, said first plurality of closely adjacent coilsforming said sidewall portion of said nose cone.
 3. The anode assemblyof claim 2 wherein said braided sleeve additionally comprises a secondplurality of closely adjacent coils, said second plurality of closelyadjacent coils being located on said trailing end portion of said anode.4. The anode assembly of claim 2 wherein said trailing portion of saidat least one pulling cable is tightly held between said nose cone andsaid anode.
 5. The anode assembly of claim 1 wherein said trailingportion of said at least one pulling cable is adhesively secured to saidanode.
 6. The anode assembly of claim 5 wherein said at least onepulling cable includes a heat shrink sleeve located on said trailingportion thereof, and wherein said heat shrink sleeve is adhesivelysecured to said anode by a holt melt glue.
 7. The anode assembly ofclaim 1 wherein said electrical conductor comprises a free end on whicha protective cap is removably mounted.
 8. The anode assembly of claim 2wherein said braided sleeve is formed of steel wire, coated steel,carbon steel or any other strong and somewhat flexible material.
 9. Theanode assembly of claim 1 wherein said at least one pulling cable isformed of steel wire.
 10. The anode assembly of claim 1 wherein saidnose cone comprises a solid walled tubular member and wherein said anodeassembly additionally comprises a braided sleeve covering said anode.11. The anode assembly of claim 10 wherein said trailing portion of saidat least one pulling cable comprises a portion of said braided sleevecovering said anode and said leading portion of said at least onepulling cable comprises a portion of said braided sleeve extending outof said nose cone.
 12. The anode assembly of claim 10 wherein saidbraided sleeve comprises a double-braided portion and a single braidedportion.
 13. The anode assembly of claim 10 wherein said braided sleeveis formed of steel wire, coated steel, carbon steel or any other strongand somewhat flexible material.
 14. The anode assembly of claim 1wherein said anode assembly has a predetermined pulling strength andwherein said anode assembly additionally comprise a break-away mechanismconnected to said leading portion of said at least one pulling cable,said break-away mechanism being arranged to break if said predeterminedpulling strength is reached to prevent damage to said anode assembly.15. The anode assembly of claim 14 wherein said anode assembly includesa second pulling cable, said second pulling cable being connected tosaid break-away mechanism to apply a pulling force to said break-awaymechanism and to said at least one pulling cable.
 16. The anode assemblyof claim 14 wherein said break-away mechanism comprises a breakable pinlocated within a housing having a leading end portion to which saidother pulling cable is secured.
 17. The anode assembly of claim 16wherein said housing is plastic and wherein said leading end of saidhousing is tapered and wherein said anode assembly additionallycomprises a section of heat shrink tubing disposed about said housingand a portion of said at least one pulling cable.
 18. A method ofinstalling an anode within the ground for a cathodic protection system,said method comprising: a) providing an anode assembly comprising ananode, a nose cone, and at least one pulling cable, said anodecomprising an elongated body having a leading end portion from which anelectrical conductor extends and a trailing end portion from which anelectrical conductor extends, said nose cone comprising a tubular memberhaving a leading portion and a trailing portion, said leading portion ofsaid nose cone having an open free end and a sidewall portion taperingin a direction from said trailing portion towards said open free end; b)disposing said leading portion of said anode within said nose cone withsaid electrical conductor extending out of said open free end and withsaid at least one pulling cable extending along at least a portion ofthe length of said anode and through said nose cone, whereupon a leadingportion of said pulling cable extends out of said open free end of saidnose cone; c) fixedly securing said nose cone to said at least onepulling cable; d) disposing the cable assembly within the ground; and e)applying a pulling force to said leading portion of said at least onepulling cable to pull said anode assembly through a path in the groundto effect its installation.
 19. The method of claim 18 wherein said nosecone comprises a braided sleeve comprising a first plurality of closelyadjacent coils, said first plurality of closely adjacent coils formingsaid sidewall portion of said nose cone.
 20. The method of claim 18wherein said anode assembly has a predetermined pulling strength andwherein said method additionally comprises: f) providing a break-awaymechanism connected to said portion of said at least one pulling cableextending out of said open free end of said nose cone, said break-awaymechanism having a second pulling cable secured to it and being arrangedto break if said predetermined pulling strength is reached to preventdamage to said anode assembly.